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Can someone explain collection_select to me in clear, simple terms?
...order(..) or something like that.
# In your example it is:
Author.all,
# then you should specify methods for generating options
:id, # this is name of method that will be called for every row, result will be set as key
:name_with_initial, # this is name of method that will be ...
How to use '-prune' option of 'find' in sh?
... test (up to and including -prune) will return false for the stuff you actually want (ie: the stuff you don't want to prune out).
Here's an example:
find . -name .snapshot -prune -o -name '*.foo' -print
This will find the "*.foo" files that aren't under ".snapshot" directories. In this example, -na...
JQuery - $ is not defined
...ge is fully loaded, and as such, before jQuery is fully loaded.
First of all, ensure, what script is call properly, it should looks like
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
and shouldn't have attributes async...
How to declare global variables in Android?
...em you are encountering is how to save state across several Activities and all parts of your application. A static variable (for instance, a singleton) is a common Java way of achieving this. I have found however, that a more elegant way in Android is to associate your state with the Application con...
public friend swap member function
...truct vector
{
void swap(vector&) { /* swap members */ }
};
Naturally, then, our class should too, right? Well, not really. The standard library has all sorts of unnecessary things, and a member swap is one of them. Why? Let's go on.
What we should do is identify what's canonical, and w...
What is “callback hell” and how and why does RX solve it?
... clear definition together with a simple example that explains what is a "callback hell" for someone who does not know JavaScript and node.js ?
...
List of Delphi language features and version in which they were introduced/deprecated
...support in enable on Linux.
C++Builder and Delphi now use the same ABI for all calls.
Delphi 10.2 Tokyo
Support for Linux server apps (Intel 64-bit using LLVM and ARC).
Assigning a dynamic arrays to a pointer using the @ operator is only allowed when hard-casting the array.
More flexible name...
Java switch statement: Constant expression required, but it IS constant
....4 Final Variables which defines a "constant variable" as follows:
We call a variable, of primitive type or type String, that is final and initialized with a compile-time constant expression (§15.28) a constant variable. Whether a variable is a constant variable or not may have implications wit...
How do I compile and run a program in Java on my Mac?
...ional Java runtime and development environment out-of-the-box with OSX, so all you have to do is write a Java program and use the built-in tools to compile and run it.
Writing Your First Program
The first step is writing a simple Java program. Open up a text editor (the built-in TextEdit app works...
Why both no-cache and no-store should be used in HTTP response?
...ce is still valid then the cache can respond with its representation, thus alleviating the need for the server to resend the entire resource.
no-store is effectively the full do not cache directive and is intended to prevent storage of the representation in any form of cache whatsoever.
I say what...